Bionic ankle joint and robot
By designing a biomimetic ankle joint with a ball-and-socket combination structure, constrained to two degrees of freedom, and equipped with an angle detection component, the problem of the difficulty in controlling spherical hinges was solved, and the direct output of angle information and connection stability were achieved.
Patent Information
- Application Number
- CN202520508503.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-21
- Publication Date
- 2026-02-03
- Estimated Expiration
- 2035-03-21
AI Technical Summary
When existing robot ankle joints use a spherical hinge design, the number of degrees of freedom increases the difficulty of control, making it difficult to directly output angle information through angle sensors.
A biomimetic ankle joint is designed, which restricts the ball joint and ball head to two degrees of freedom by means of a combination structure, and sets up an angle detection component, including first and second angle detection components, and uses first and second encoders in conjunction with a magnetic ring to output angle information.
It achieves stable motion of the spherical hinge, simplifies control, can directly output angle information, and improves connection reliability and human-likeness.
Smart Images
Figure CN223863811U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of robotics technology, and in particular to a bionic ankle joint and robot. Background Technology
[0002] The ankle joint is an important weight-bearing joint in the lower limbs, located between the lower leg and foot. It bears most of the body's weight and has a high degree of flexibility. The ankle joint has two degrees of freedom, allowing for various movements such as foot flexion, dorsiflexion, inversion, and eversion. During walking and running, the ankle joint needs to constantly adjust to adapt to uneven ground and changes in body movement.
[0003] Currently, the ankle joints of humanoid robots generally adopt the cross-axis solution. Its advantage is that the angle in two directions can be directly output through the encoder. Its disadvantage is that the cross-axis solution involves multiple connectors and bearings, which makes the overall structure relatively complex, the connection rigidity is poor, the connectors are prone to loosening or breakage, the bearings are prone to wear or damage, and the size is large, resulting in high production and manufacturing costs.
[0004] The ankle joint of a humanoid robot can also use a spherical hinge design. Its advantages include a more compact structure, and stable movement under heavy loads or high-speed motion, making it less prone to damage and highly reliable. The disadvantages are that the spherical hinge increases the degree of freedom, making control more difficult, and it's harder to directly output angle information via an angle sensor.
[0005] In summary, when existing robot ankle joints use spherical hinges, the increased degrees of freedom of the spherical hinges make control more difficult, and it is hard to directly output angle information through angle sensors. Utility Model Content
[0006] In view of this, it is necessary to provide a bionic ankle joint and robot to solve the problem that the spherical hinge has many degrees of freedom, which increases the difficulty of control and makes it difficult to directly output angle information through an angle sensor.
[0007] On one hand, this utility model provides a bionic ankle joint, including a ball socket, a ball head, and a connecting component; the top of the ball socket has a spherical groove, and its sidewall has an arc-shaped sliding groove communicating with the spherical groove; the ball head is built into the spherical groove and is connected to the spherical groove; the connecting component includes a rotating part and a sliding part, one side of the rotating part is fixedly connected to the ball head, the other side of the rotating part extends into the arc-shaped sliding groove and is rotatably connected to the sliding part, the rotation axis of the rotating part is arranged radially along the ball head, and the sliding part is slidably connected to the arc-shaped sliding groove.
[0008] Furthermore, the rotating part is a first spindle, the sliding part is a pressure plate slider, the first spindle is arranged radially along the ball head, the pressure plate slider has a connecting hole inside, the connecting assembly also includes a first bearing installed in the connecting hole, and the first spindle is connected to the inner ring of the first bearing.
[0009] Furthermore, there are two first mandrels and two pressure plate sliders. The two first mandrels are coaxially arranged and respectively located on both sides of the ball head. The opposite ends of the two first mandrels are fixedly connected to the ball head, and the opposite ends of the two first mandrels are rotatably connected to the two pressure plate sliders respectively. The two pressure plate sliders are slidably connected to the two arc-shaped grooves opened on both sides of the ball socket respectively.
[0010] Furthermore, it also includes a first angle detection component, which includes a first mounting bracket, a first encoder, and a first magnetic ring. The first mounting bracket is fixedly connected to the sliding part. The first encoder is mounted on the side of the first mounting bracket near the rotating part. The first magnetic ring is mounted on the side of the rotating part near the first encoder and is located on the rotation axis of the rotating part.
[0011] Furthermore, it also includes a second angle detection component, which includes a second spindle, a second mounting bracket, a second encoder, and a second magnetic ring. The second spindle is arranged perpendicular to the rotation axis of the rotating part and the plane where the arc-shaped slide groove is located, and the second spindle is arranged radially along the rotating part. One end of the second spindle is connected to the outer wall of the ball socket, and the other end of the second spindle extends into the second mounting bracket and is fixedly connected to the second magnetic ring. The second mounting bracket is fixedly connected to the sliding part, and the second encoder is mounted on the second mounting bracket and is positioned directly opposite the second magnetic ring.
[0012] Furthermore, the second angle detection component also includes a second bearing installed in a connection hole on the second mounting bracket, and the second spindle is connected to the inner ring of the second bearing.
[0013] Furthermore, the second angle detection component also includes a linkage component, which is an arc-shaped plate structure. The linkage component is spaced apart from the ball socket and connects the second mounting bracket and the sliding part.
[0014] Furthermore, the ball socket includes a connecting seat and a pressure cap. The bottom of the connecting seat is used to connect to the foot model, the top of the connecting seat has a first hemispherical groove, the bottom of the pressure cap has a second hemispherical groove, and the top of the pressure cap has an opening that communicates with the second hemispherical groove. The connecting seat and the pressure cap are detachably connected. When the connecting seat and the pressure cap are connected, the first hemispherical groove and the second hemispherical groove are mated to form the spherical groove.
[0015] Furthermore, it also includes a connecting rod and a connecting ring. The bottom end of the connecting rod passes through the opening and is fixedly connected to the ball head. The top end of the connecting rod is used to connect the leg model. The connecting ring is fixedly disposed on the outer wall of the connecting rod and has multiple connecting holes.
[0016] On the other hand, this utility model embodiment also provides a robot, including a robot body equipped with the bionic ankle joint described above.
[0017] Compared with the prior art, in implementation, the sliding part allows the ball head to rotate relative to the ball socket along the extension direction of the arc groove, which is the first rotation direction. At the same time, the rotating part and the sliding part are rotatably connected, and the rotation axis of the rotating part is set along the radial direction of the ball head, thereby driving the ball head to rotate relative to the ball socket in the second rotation direction. By setting the ball head and ball socket to have only two degrees of freedom in the rotation direction, it is easy to control the rotation direction of the ball head so that the angle sensor can output angle information. Attached Figure Description
[0018] Figure 1 A schematic diagram of the external structure of the bionic ankle joint and the robot as a whole provided for an embodiment of this utility model;
[0019] Figure 2 A top view of the bionic ankle joint and the robot as a whole provided for an embodiment of this utility model;
[0020] Figure 3 The bionic ankle joint and robot provided in this embodiment of the utility model Figure 2 Enlarged diagram of section A in the middle;
[0021] Figure 4 This is a schematic diagram showing the connection between the ball socket and the ball head in the bionic ankle joint and robot provided in this embodiment of the utility model. Detailed Implementation
[0022] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which form part of this application and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.
[0023] Both cross hinges and ball joints, commonly used in robots, have their limitations. Under high loads, the connectors of the cross axis are prone to loosening or breakage, and the bearings are easily worn or damaged. Ball joints offer high reliability but increase the degree of freedom, making control more difficult, and it is also difficult to directly output angle information through angle sensors.
[0024] Therefore, this application improves the ball joint structure, constrains the three degrees of freedom of the ball joint into two degrees of freedom, and cleverly arranges angle sensors to decouple the angle relationship. It has the advantages of compact space, high connection reliability and human-like appearance, which will be described in detail below.
[0025] like Figure 1-3 As shown, this embodiment of the present invention provides a bionic ankle joint, including a ball socket 100, a ball head 200, and a connecting component 300; the top of the ball socket 100 is formed with a spherical groove 110, and its sidewall is formed with an arcuate sliding groove 120 communicating with the spherical groove 110; the ball head 200 is built into the spherical groove 110 and is connected to the spherical groove 110; the connecting component 300 includes a rotating part 310 and a sliding part 320, one side of the rotating part 310 is fixedly connected to the ball head 200, and the other side of the rotating part 310 extends into the arcuate sliding groove 120 and is rotatably connected to the sliding part 320, the rotation axis of the rotating part 310 is arranged radially along the ball head 200, and the sliding part 320 is slidably connected to the arcuate sliding groove 120.
[0026] In practice, the sliding part 320 allows the ball head 200 to rotate relative to the ball socket 100 along the extension direction of the arc groove, which is the first rotation direction. At the same time, the rotating part 310 is rotatably connected to the sliding part 320, and the rotation axis of the rotating part 310 is set along the radial direction of the ball head 200, thereby driving the ball head 200 to rotate relative to the ball socket 100 in the second rotation direction. With the above settings, the ball head 200 and the ball socket 100 can only have two degrees of freedom in rotation, which makes it easy to control the rotation direction of the ball head 200 so that the angle sensor can output angle information.
[0027] In this embodiment, the ball socket 100 and the ball head 200 form a spherical hinge. To limit the degree of freedom of rotation of the ball head 200, the side wall of the ball socket 100 is formed with an arc-shaped groove 120 that communicates with the spherical groove 110. Through the provided connecting component 300, the ball head 200 can be limited to rotate along the extension direction of the arc-shaped groove 120 or in a direction perpendicular to the arc-shaped groove 120.
[0028] Among them, the ball socket 100 is made of non-metallic material with good lubricity and high strength, while the ball head 200 is made of metallic material.
[0029] The connecting component 300 in this embodiment includes a rotating part 310 and a sliding part 320. One side of the rotating part 310 is fixedly connected to the ball head 200, and the other side of the rotating part 310 extends into the arc-shaped groove 120 and is rotatably connected to the sliding part 320. The rotation axis of the rotating part 310 is arranged radially along the ball head 200, and the sliding part 320 is slidably connected to the arc-shaped groove 120.
[0030] In this embodiment, the rotating part 310 is a first spindle, the sliding part 320 is a pressure plate slider, the first spindle is arranged radially along the ball head 200, the pressure plate slider has a connecting hole inside, the connecting assembly 300 also includes a first bearing 330 installed in the connecting hole, and the first spindle is connected to the inner ring of the first bearing 330.
[0031] To improve the stability of the ball head 200 rotation, there are two first spindles and two pressure plate sliders in this embodiment. The two first spindles are coaxially arranged and respectively arranged on both sides of the ball head 200. The opposite ends of the two first spindles are fixedly connected to the ball head 200, and the opposite ends of the two first spindles are rotatably connected to the two pressure plate sliders respectively. The two pressure plate sliders are slidably connected to the two arc-shaped grooves 120 opened on both sides of the ball socket 100 respectively.
[0032] To detect the angle of rotation of the ball head 200 along the direction perpendicular to the arc-shaped slide groove 120, this embodiment also includes a first angle detection component 400. The first angle detection component 400 includes a first mounting bracket 410, a first encoder 420, and a first magnetic ring 430. The first mounting bracket 410 is fixedly connected to the sliding part 320. The first encoder is mounted on the side of the first mounting bracket 410 near the rotating part 310. The first magnetic ring 430 is mounted on the side of the rotating part 310 near the first encoder 420 and is located on the rotation axis of the rotating part 310.
[0033] To detect the angle of rotation of the ball head 200 along the extension direction of the arc-shaped slide groove 120, this embodiment also includes a second angle detection component 500. The second angle detection component 500 includes a second spindle 510, a second mounting bracket 520, a second encoder 530, and a second magnetic ring 540. The second spindle 510 is arranged perpendicular to the rotation axis of the rotating part 310 and the plane where the arc-shaped slide groove 120 is located, and the second spindle 510 is arranged radially along the rotating part 310. One end of the second spindle 510 is connected to the outer wall of the ball socket 100, and the other end of the second spindle 510 extends into the second mounting bracket 520 and is fixedly connected to the second magnetic ring 540. The second mounting bracket 520 is fixedly connected to the sliding part 320. The second encoder 530 is mounted on the second mounting bracket 520 and is positioned directly opposite the second magnetic ring 540.
[0034] like Figure 2-3As shown, during ankle joint movement, the ball head 200 is the stationary axis. When the ball socket 100 performs pitching motion, the pressure plate slider is stationary relative to the arc-shaped groove 120, while simultaneously rotating relative to the first spindle. The first encoder 420 and the first magnetic ring 430 rotate relative to each other, thus outputting the pitch angle information. When the ball socket 100 performs lateral movement, the pressure plate slider is stationary relative to the first spindle, while simultaneously sliding and rotating within the arc-shaped groove 120. The pressure plate slider drives the second encoder 530 to rotate around the second spindle 510, and the second encoder 530 rotates relative to the second magnetic ring 540, thus outputting the roll angle information.
[0035] In one embodiment, the second angle detection component 500 further includes a second bearing 550 installed in a connection hole on the second mounting bracket 520, and the second spindle 510 is connected to the inner ring of the second bearing 550.
[0036] To facilitate the connection between the second mounting bracket 520 and the sliding part 320, in one embodiment, the second angle detection component 500 further includes a linkage member 521. The linkage member 521 is an arc-shaped plate structure. The linkage member 521 is spaced apart from the ball socket 100 and connects the second mounting bracket 520 and the sliding part 320.
[0037] To facilitate the installation of the ball head 200, in one embodiment, the ball socket 100 includes a connecting seat 130 and a pressure cap 140. The bottom of the connecting seat 130 is used to connect the foot model, the top of the connecting seat 130 has a first hemispherical groove, the bottom of the pressure cap 140 has a second hemispherical groove, and the top of the pressure cap 140 has an opening communicating with the second hemispherical groove. The connecting seat 130 and the pressure cap 140 are detachably connected. When the connecting seat 130 and the pressure cap 140 are connected, the first hemispherical groove and the second hemispherical groove are joined to form a spherical groove 110.
[0038] like Figure 4 As shown, this embodiment also includes a connecting rod 210 and a connecting ring 220. The bottom end of the connecting rod 210 passes through the opening and is fixedly connected to the ball head 200. The top end of the connecting rod 210 is used to connect the leg model. The connecting ring 220 is fixedly set on the outer wall of the connecting rod 210, and multiple connecting holes are opened on the connecting ring 220.
[0039] This utility model embodiment also provides a robot, including a robot body equipped with the bionic ankle joint described above.
[0040] Compared with the prior art: By setting the sliding part 320, the ball head 200 can rotate relative to the ball socket 100 along the extension direction of the arc groove, which is the first rotation direction. At the same time, the rotating part 310 is rotatably connected to the sliding part 320, and the rotation axis of the rotating part 310 is set along the radial direction of the ball head 200, thereby driving the ball head 200 to rotate relative to the ball socket 100 in the second rotation direction. By setting the ball head 200 and the ball socket 100 to have only two degrees of freedom in the rotation direction, it is convenient to control the rotation direction of the ball head 200 so that the angle sensor can output angle information.
[0041] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present utility model should be included within the protection scope of the present utility model.
Claims
1. A bionic ankle joint, characterized in that, include: The ball socket has a spherical groove formed at its top and an arc-shaped sliding groove formed on its sidewall that communicates with the spherical groove. A ball head, which is built into the spherical groove and connected to the spherical groove; A connecting assembly includes a rotating part and a sliding part. One side of the rotating part is fixedly connected to the ball head, and the other side of the rotating part extends into the arc-shaped groove and is rotatably connected to the sliding part. The rotation axis of the rotating part is arranged radially along the ball head, and the sliding part is slidably connected to the arc-shaped groove.
2. The bionic ankle joint according to claim 1, characterized in that, The rotating part is a first spindle, the sliding part is a pressure plate slider, the first spindle is arranged radially along the ball head, the pressure plate slider has a connecting hole inside, the connecting assembly also includes a first bearing installed in the connecting hole, and the first spindle is connected to the inner ring of the first bearing.
3. The bionic ankle joint according to claim 2, characterized in that, There are two first mandrels and two pressure plate sliders. The two first mandrels are coaxially arranged and respectively located on both sides of the ball head. The opposite ends of the two first mandrels are fixedly connected to the ball head, and the opposite ends of the two first mandrels are rotatably connected to the two pressure plate sliders respectively. The two pressure plate sliders are slidably connected to the two arc-shaped grooves opened on both sides of the ball socket respectively.
4. The bionic ankle joint according to claim 1, characterized in that, It also includes a first angle detection component, which includes a first mounting bracket, a first encoder, and a first magnetic ring. The first mounting bracket is fixedly connected to the sliding part. The first encoder is mounted on the side of the first mounting bracket near the rotating part. The first magnetic ring is mounted on the side of the rotating part near the first encoder and is located on the rotation axis of the rotating part.
5. The bionic ankle joint according to claim 1, characterized in that, It also includes a second angle detection component, which includes a second spindle, a second mounting bracket, a second encoder, and a second magnetic ring. The second spindle is arranged perpendicular to the rotation axis of the rotating part and the plane where the arc-shaped slide groove is located, and the second spindle is arranged radially along the rotating part. One end of the second spindle is connected to the outer wall of the ball socket, and the other end of the second spindle extends into the second mounting bracket and is fixedly connected to the second magnetic ring. The second mounting bracket is fixedly connected to the sliding part, and the second encoder is mounted on the second mounting bracket and is positioned directly opposite the second magnetic ring.
6. The bionic ankle joint according to claim 5, characterized in that, The second angle detection component also includes a second bearing installed in a connection hole on the second mounting bracket, and the second spindle is connected to the inner ring of the second bearing.
7. The bionic ankle joint according to claim 5, characterized in that, The second angle detection component further includes a linkage component, which is an arc-shaped plate structure. The linkage component is spaced apart from the ball socket and connects the second mounting bracket and the sliding part.
8. The bionic ankle joint according to claim 1, characterized in that, The ball socket includes a connecting seat and a pressure cap. The bottom of the connecting seat is used to connect to the foot model. A first hemispherical groove is formed on the top of the connecting seat. A second hemispherical groove is formed on the bottom of the pressure cap. An opening communicating with the second hemispherical groove is provided on the top of the pressure cap. The connecting seat and the pressure cap are detachably connected. When the connecting seat and the pressure cap are connected, the first hemispherical groove and the second hemispherical groove are mated to form the spherical groove.
9. The bionic ankle joint according to claim 8, characterized in that, It also includes a connecting rod and a connecting ring. The bottom end of the connecting rod passes through the opening and is fixedly connected to the ball head. The top end of the connecting rod is used to connect the leg model. The connecting ring is fixedly set on the outer wall of the connecting rod and has multiple connecting holes.
10. A robot, characterized in that, Includes a robotic body equipped with a bionic ankle joint as described in any one of claims 1-9.